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Reusable Pagination System

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Since pagination always looks the same, no matter what you're listing, I really want to organize my code so that pagination is effortless in the future. This took way too many lines of code.

Inside of the Pagination/ directory, create a new PHP class called PaginationFactory. There, add a new public function createCollection() method: this will create the entire final PaginatedCollection object for some collection resource. To do this, we'll need to pass it a few things, starting with the $qb and the $request - we'll use that to find the current page. The method will also need to know the route for the links and any $routeParams it needs:

55 lines src/AppBundle/Pagination/PaginationFactory.php
... lines 1 - 2
namespace AppBundle\Pagination;
use Doctrine\ORM\QueryBuilder;
... lines 6 - 7
use Symfony\Component\HttpFoundation\Request;
... lines 9 - 10
class PaginationFactory
{
... lines 13 - 19
public function createCollection(QueryBuilder $qb, Request $request, $route, array $routeParams = array())
{
... lines 22 - 53
}
}

Go back to ProgrammerController, copy the logic, remove it and put it into PaginationFactory. Add the missing use statements: by auto-completing the classes DoctrineORMAdapter and Pagerfanta. Now, delete $route and $routeParams since those are passed as arguments. Remove the $qb variable for the same reason:

55 lines src/AppBundle/Pagination/PaginationFactory.php
... lines 1 - 5
use Pagerfanta\Adapter\DoctrineORMAdapter;
use Pagerfanta\Pagerfanta;
... lines 8 - 10
class PaginationFactory
{
... lines 13 - 19
public function createCollection(QueryBuilder $qb, Request $request, $route, array $routeParams = array())
{
$page = $request->query->get('page', 1);
$adapter = new DoctrineORMAdapter($qb);
$pagerfanta = new Pagerfanta($adapter);
$pagerfanta->setMaxPerPage(10);
$pagerfanta->setCurrentPage($page);
$programmers = [];
foreach ($pagerfanta->getCurrentPageResults() as $result) {
$programmers[] = $result;
}
$paginatedCollection = new PaginatedCollection($programmers, $pagerfanta->getNbResults());
$createLinkUrl = function($targetPage) use ($route, $routeParams) {
return $this->router->generate($route, array_merge(
$routeParams,
array('page' => $targetPage)
));
};
$paginatedCollection->addLink('self', $createLinkUrl($page));
$paginatedCollection->addLink('first', $createLinkUrl(1));
$paginatedCollection->addLink('last', $createLinkUrl($pagerfanta->getNbPages()));
if ($pagerfanta->hasNextPage()) {
$paginatedCollection->addLink('next', $createLinkUrl($pagerfanta->getNextPage()));
}
if ($pagerfanta->hasPreviousPage()) {
$paginatedCollection->addLink('prev', $createLinkUrl($pagerfanta->getPreviousPage()));
}
return $paginatedCollection;
}
}

In fact, move that back to ProgrammerController: we'll want it in a minute:

189 lines src/AppBundle/Controller/Api/ProgrammerController.php
... lines 1 - 18
class ProgrammerController extends BaseController
{
... lines 21 - 76
public function listAction(Request $request)
{
$qb = $this->getDoctrine()
->getRepository('AppBundle:Programmer')
->findAllQueryBuilder();
... lines 82 - 84
$response = $this->createApiResponse($paginatedCollection, 200);
return $response;
}
... lines 89 - 187
}

The only other problem here is $this->generateUrl(): that method does not exist outside of the controller. That's ok: since we do need to generate URLs, this just means we need the router. Add a __construct() function at the top with RouterInterface as an argument. I'll use the Alt + enter PHPStorm shortcut to create and set that property:

55 lines src/AppBundle/Pagination/PaginationFactory.php
... lines 1 - 8
use Symfony\Component\Routing\RouterInterface;
class PaginationFactory
{
private $router;
public function __construct(RouterInterface $router)
{
$this->router = $router;
}
... lines 19 - 54
}

Back inside createCollection(), change $this->generateUrl() to $this->router->generate():

55 lines src/AppBundle/Pagination/PaginationFactory.php
... lines 1 - 10
class PaginationFactory
{
... lines 13 - 19
public function createCollection(QueryBuilder $qb, Request $request, $route, array $routeParams = array())
{
... lines 22 - 35
$createLinkUrl = function($targetPage) use ($route, $routeParams) {
return $this->router->generate($route, array_merge(
$routeParams,
array('page' => $targetPage)
));
};
... lines 42 - 53
}
}

Our work in this class is done! Next, register this as service in app/config/services.yml - let's call it pagination_factory. How creative! Set the class to PaginationFactory and pass one key for arguments: @router:

29 lines app/config/services.yml
... lines 1 - 5
services:
... lines 7 - 25
pagination_factory:
class: AppBundle\Pagination\PaginationFactory
arguments: ['@router']

Tip

If you're using Symfony 3.3, your app/config/services.yml contains some extra code that may break things when following this tutorial! To keep things working - and learn about what this code does - see https://knpuniversity.com/symfony-3.3-changes

Copy the service name and open ProgrammerController to hook this all up. Now, just use $paginatedCollection = $this->get('pagination_factory')->createCollection() and pass it the 4 arguments: $qb, $request, the route name - api_programmers_collection - and the route params:

189 lines src/AppBundle/Controller/Api/ProgrammerController.php
... lines 1 - 18
class ProgrammerController extends BaseController
{
... lines 21 - 76
public function listAction(Request $request)
{
... lines 79 - 81
$paginatedCollection = $this->get('pagination_factory')
->createCollection($qb, $request, 'api_programmers_collection');
... lines 84 - 87
}
... lines 89 - 187
}

Actually, most of the time you won't have route params. So head back into PaginationFactory and make that argument optional:

55 lines src/AppBundle/Pagination/PaginationFactory.php
... lines 1 - 10
class PaginationFactory
{
... lines 13 - 19
public function createCollection(QueryBuilder $qb, Request $request, $route, array $routeParams = array())
{
... lines 22 - 53
}
}

Much better.

Now, PhpStorm should be happy... but it's still not! It looks more like someone stole it's ice cream. Ah, I forgot to return $paginatedCollection in PaginationFactory:

55 lines src/AppBundle/Pagination/PaginationFactory.php
... lines 1 - 10
class PaginationFactory
{
... lines 13 - 19
public function createCollection(QueryBuilder $qb, Request $request, $route, array $routeParams = array())
{
... lines 22 - 52
return $paginatedCollection;
}
}

PhpStorm was complaining that createCollection() didn't look like it returned anything... and it was right! The robots are definitely taking over.

Run the test to see if we broke anything:

./bin/phpunit -c app --filter filterGETProgrammersCollectionPaginated

We didn't! What a delightful surprise.

Now, if you want some sweet pagination, just create a QueryBuilder, pass it into the PaginationFactory, pass that to createApiResponse and then go find some ice cream.

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Default user avatar
Default user avatar Neandher Carlos | posted 5 years ago | edited

Hi,

In my case, i applied this <strong>rawurldecode</strong> function to fix query params encoding:


            return rawurldecode($this->router->generate(
                $route,
                array_merge(
                    $routeParams,
                    array('page' => $targetPage)
                )
            ));

Before rawurldecode: 


"_links": {
    "self": "/app_dev.php/api/comments?sorting%5BcreatedAt%5D=desc&filter=%C3%A1&page=1",
    "first": "/app_dev.php/api/comments?sorting%5BcreatedAt%5D=desc&filter=%C3%A1&page=1",
    "last": "/app_dev.php/api/comments?sorting%5BcreatedAt%5D=desc&filter=%C3%A1&page=2",
    "next": "/app_dev.php/api/comments?sorting%5BcreatedAt%5D=desc&filter=%C3%A1&page=2"
  }

After rawurldecode:


"_links": {
    "self": "/app_dev.php/api/comments?sorting[createdAt]=desc&filter=á&page=1",
    "first": "/app_dev.php/api/comments?sorting[createdAt]=desc&filter=á&page=1",
    "last": "/app_dev.php/api/comments?sorting[createdAt]=desc&filter=á&page=2",
    "next": "/app_dev.php/api/comments?sorting[createdAt]=desc&filter=á&page=2"
  }

=)

11 Reply
Jovan P. Avatar
Jovan P. Avatar Jovan P. | posted 5 years ago

This is like 20th lesson or so I listened that was recorded by you. Must say, I enjoy every second of those. Very knowledgeable, funny, fast... just keep doing what you're doing :)

Reply
weaverryan Avatar

Cheers Jovan :)

1 Reply
Nizar Avatar

Hello Ryan,
In my project I have a back office to create sites and their content pars example images.
These images are sent to the server vai a form and I put them in a folder:
web / uplaod / siteName / iamges /.
knowing that these images are on a server 1 and I want to create a cron to move them later on another server 2.

can I create a cron myself by exploiting the power of symfony?

Reply
MolloKhan Avatar

Hey Nizar

That's totally posible to do in Symfony (except the part of registering a CRON job into your server). You can create a Symfony command that actually move those files, and then, set up a CRON job that executes that command whenever you need it.
You can read more info about creating a Symfony command here: https://symfony.com/doc/cur...

Cheers!

-1 Reply
Chuck norris Avatar
Chuck norris Avatar Chuck norris | posted 5 years ago

Hi Ryan,

It's really nothing, but for consistency, shouldn't you rename "programmers" variable into "items" inside createCollection method ?

Reply
weaverryan Avatar

Ha, oh totally - you're 100% right :). I hadn't even noticed this!

Reply
Nizar Avatar

Hi,

I want to use a pagintion in my project but I hesitate between : KnpPaginatorBundle and WhiteOctoberPagerfantaBundle

you advise me which one.

thanks for your replay

Reply
weaverryan Avatar

Hi Nizar!

They're both good - at this time, I'd slightly recommend Knp, but they are both maintained quite well :).

Cheers!

Reply
Nizar Avatar

Thanks ryan

Reply
Nizar Avatar

Hi ryan,

I have in my project a document entity that has a ManytoOne type relationship with another image entity. So I have to create an interface to send images to the server for the document entity
and I would like to use a bundle that contains the DropZone plugin for example.

I develop this feature myself? or I use a bundle?
if not, do you recommend which bundle?
thanks for the answer.

Reply
Victor Avatar

Hey Ali,

If there's a good bundle - you better to use it instead of re-doing things manually. Third-party bundles have some advantages like you don't need to spend your time for writing this feature, good bundles are well tested, etc. I personally do not use any bundles that has integration with DropZone, but after google it quickly I found a one, so take a look at: https://github.com/1up-lab/... that is pretty popular on GitHub and have a lot of integration with other JS uploaders.

Cheers!

Reply
Nizar Avatar

thanks Victor

Reply
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This tutorial uses an older version of Symfony. The concepts of REST and serialization are still valid, but I recommend using API Platform in new Symfony apps.
Symfony 3

What PHP libraries does this tutorial use?

// composer.json
{
    "require": {
        "php": ">=5.3.3",
        "symfony/symfony": "2.6.*", // v2.6.11
        "doctrine/orm": "~2.2,>=2.2.3,<2.5", // v2.4.7
        "doctrine/dbal": "<2.5", // v2.4.4
        "doctrine/doctrine-bundle": "~1.2", // v1.4.0
        "twig/extensions": "~1.0", // v1.2.0
        "symfony/assetic-bundle": "~2.3", // v2.6.1
        "symfony/swiftmailer-bundle": "~2.3", // v2.3.8
        "symfony/monolog-bundle": "~2.4", // v2.7.1
        "sensio/distribution-bundle": "~3.0,>=3.0.12", // v3.0.21
        "sensio/framework-extra-bundle": "~3.0,>=3.0.2", // v3.0.7
        "incenteev/composer-parameter-handler": "~2.0", // v2.1.0
        "hautelook/alice-bundle": "0.2.*", // 0.2
        "jms/serializer-bundle": "0.13.*", // 0.13.0
        "white-october/pagerfanta-bundle": "^1.0" // v1.2.4
    },
    "require-dev": {
        "sensio/generator-bundle": "~2.3", // v2.5.3
        "behat/behat": "~3.0", // v3.0.15
        "behat/mink-extension": "~2.0.1", // v2.0.1
        "behat/mink-goutte-driver": "~1.1.0", // v1.1.0
        "behat/mink-selenium2-driver": "~1.2.0", // v1.2.0
        "phpunit/phpunit": "~4.6.0" // 4.6.4
    }
}
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